While a new Liberace Museum still hasn’t appeared, you can see some of the museum’s collection at the Cosmopolitan now through January 2, 2014.  The Too Much of a Good Thing Is Wonderful: Liberace and the Art of Costume exhibit features Liberace’s rhinestone covered Roadster and Baldwin grand piano as well as a selection of his costumes, candelabras, performance videos and other artifacts.

The main exhibit is in the Pop-Up Chapel space, near the Strip entrance.  You can find his rhinestone covered Roadster on the casino floor nearby.  Las Vegas Weekly has many good photos of the exhibit online here.

The exhibit is open 3pm – 10pm until January 2, 2014.
Admission is free, but donations are accepted.
For more information about the exhibit, call 702-698-7640

Update:
The exhibit has been extended through February 28th, 2014

Update:
The exhibit is now closed. The Lucky Cat is now in that space.